Citizens of parktown are worried by the increased frequency of serious crimes committed by local teenagers. In response, the city government has instituted a series of measures designed to keep teenagers at home in the late evening. Even if the measures succeed in keeping teenagers at home, however, they are unlikely to affect the problem that concerns citizens, since most crimes committed by local teenagers take place between 3pm and 6pm

Which of the following,if true, most substantially weakens the argument ?
GPrep Q

1) Similar measures adopted in other place have failed to reduce the no of teenagers in the late evening
2) Crimes committed by teenagers in afternoon are mostly small thefts and inconsequential vandalism
3) teenagers are much less likely to commit serious crimes when they are at home than when they are not at home
4) Any decrease in the need for police patrols in late evening would not mean that there could be more intensive patrolling in the afternoon
5) The schools in parktown have introduced a number of after school programs that will be available to teenagers until 6pm on weekday afternoons

OA : B

WHy not C . I chose D in a rush looking at words..'police patrolling ..afternoon'..

Thanks

Problem is that city people are concerned with the increase of frequency in serious crimes. The word serious is the key here.

Conclusion is that the measure to keep children after 6 pm/ late evening will not help because most crime happens between 3 and 6

We have to prove that measures will be effective. What if the crimes that happen between 3 and 6 are petty and inconsequential? Not serious any more?? measures are effective. Hence B

To me A,C, D are out of scope. E makes an attempt but because E does not tell us whether the teens will stay in school. An assumption needs to be made to weaken the conclusion. Hence B is better

ron,

let's assume a situation when all strategies have failed. this is what i would do. please validate my thought process.

1) Similar measures adopted in other place have failed to reduce the no of teenagers in the late evening - i am not bothered bothered about other place

2) Crimes committed by teenagers in afternoon are mostly small thefts and inconsequential vandalism

3) teenagers are much less likely to commit serious crimes when they are at home than when they are not at home - very generalised

4) Any decrease in the need for police patrols in late evening would not mean that there could be more intensive patrolling in the afternoon - police patrols? no where in the argument. out of the window.

5) The schools in parktown have introduced a number of after school programs that will be available to teenagers until 6pm on weekday afternoons - what about the weekends?

As I am unable to eliminate (2) - mark (2).

here is my question. is it ok to eliminate WEAKEN answer choices by looking at terms that are out of scope. Ex : police patrols in choice (4). I am stressing here on TERMS because i took time to comprehend (4). so, is it fine to eliminate WEAKEN answer choices on OUT OF SCOPE TERMS?

ron,

could you please help me fix this?

In strengthen or weaken questions it is ok for an answer choice to bring in new info not stated in the argument and it almost always does. For example (not limited to just this) Out of scope would be something that weakens a different argument or does not apply in anyway to what we are trying to weaken.

hi ashish.jere,

i think the point we missed he is "serious crime"

argument is about "serious crime" , but the author concluded by saying most crimes takes place in between 3pm and 6pm.

So smart "GMAT test makers" has deployed a trap in the name of (C) for those who didn't notice this. :-)

yep, this is it.

takeaway:
when you read critical reasoning passages, you MUST be ALERT FOR ANY AND ALL DIFFERENCES BETWEEN SPECIFICS.
you have to have this mentality in which there is absolutely no such thing as "kind of related".
given 2 specifics, they are either (a) exactly the same, or (b) not the same. this is the way you have to think; there is no "in between".

in this passage, "crimes" and "serious crimes" are Not The Same - but this passage DEPENDS on treating them AS IF THEY WERE the same.
therefore, choice (b) weakens the argument by highlighting the difference between the two.

Thanks Ron. Is this trick (treating them AS IF THEY WERE the same) used by GMAT test writers only in weaken CR type? If no, what other CR type can i expect to see the same trick?

actually, by far the most common context in which it's used is find the assumption questions.

this is a very common type of assumption: a passage will treat two different concepts as though they were actually the same. the "assumption on which the argument depends" (i.e., the assumption you're supposed to find) will be some sort of statement connecting those two otherwise unconnected statements.

--

MOST "weaken" problems act by undermining ASSUMPTIONS, anyway, se it's a good bet that any trick they use on a "weaken" problem can also be applied to a "find the assumption" problem (and vice versa).

hi Ron,

Is E wrong because it fails to account for the weekends?
Thanks.

nah. (e) is wrong because it's completely irrelevant to the actual issue treated in the passage.

note the passage's conclusion:
Even if the measures succeed in keeping teenagers at home, however, they are unlikely to affect the problem that concerns citizens

the passage is solely concerned with the effect of the new measures. therefore, we don't care if there are other programs that might have a mitigating effect on the crime rate.

Ron - thank you for your feedback!
another query....although i hate to stir up the past here...
but i've seen this trend in certain CR questions...basically, answer choice B is directly negating one of the premises in the argument. Am I interpreting it right? I ask because I've seen similar correct answer types elsewhere...and i've trained myself to think that all the premises given in CR question are correct.

B does not contradict a premise. Rather, it references two different premises (increased crime and crimes between 3 and 6) and helps point out that they aren't necessarily referring to the same thing..

_________________
Tim Sanders
Manhattan GMAT Instructor

I understand B , but I don't get why C isn't right as well.


C) teenagers are much less likely to commit serious crimes when they are at home than when they are not at home

That weakens the conclusion that serious crimes will not be reduced by the program.

Here's the problem: the plan will only keep them at home at night, and the argument tells us that most of the crimes committed by teenagers occur between 3 and 6pm. Thus, keeping them home during a time in which they are unlikely to commit a crime will probably not reduce the incidence of serious crimes.

_________________
Jamie Nelson
ManhattanGMAT Instructor